Surface distributed acoustic sensing (S-DAS) for high resolution near surface characterization

Distributed acoustic sensing (DAS) technology offers a wide range of applications in geophysics. In the oil and gas industry, the use of DAS is well established in the borehole domain, but it is only in the last few years that the use of DAS fiber optics as seismic sensor deployed on the surface has been experimented. This novel technology offers advantages in dense sampling at low cost; nevertheless, when deployed on the surface, DAS configurations pose specific challenges. Surface DAS data have been collected during the acquisition of a 3D land large-scale field test, the data have been processed focusing on the latest advancement in the use of surface-waves analysis and inversion. The result from the surface DAS recording is compared and validated with co-located multicomponent (3C) geophones and conventional high-density surface seismic nodal acquisition. The contribution of multi-modal dispersion curves analysis and inversion has been validated with the sub-surface profiling from non-seismic measurements such as resistivity acquisitions (i.e. electrical resistivity tomography, ERT).